A view of south-bound traffic from the decorated juniper tree on I-17, north of the Sunset Point rest area.

(Photo by Nadine Arroyo Rodriguez-KJZZ)

The juniper tree north of Sunset Point rest area mysteriously decorated again for the holiday season.

(Photo by Nadine Arroyo Rodriguez-KJZZ)

ADOT Spokesperson Doug Nintzel poses near I-17 tree north of the Sunset Point rest area. The tree has been mysteriously decorated during the holiday season for about 30 years.

(Photo by Nadine Arroyo Rodriguez-KJZZ)

Decorations adorn the yearly decorated juniper tree on I-17.

(Photo by Nadine Arroyo Rodriguez-KJZZ)

The barrels and plastic pipes are part of a makeshift irrigation system for the tree.

The holiday season is about celebrations and gift giving surprises. Well, there is a surprise Arizonans receive every holiday season. You may have noticed it on the way to northern Arizona.

It has become an unofficial holiday tradition in Arizona. A juniper tree in the middle of Interstate 17, decorated every year for the holiday season. Did You Know the tree has been trimmed for about 30 years, and who does it is a mystery?

“We’ve got the flasher on. I’ve got a truck, so, I’m gonna pull over to the left now. Try to keep us safe," said Arizona Department of Transportation spokesperson Doug Nintzel on our visit to the tree.

The tree is located north of the Sunset Point rest area, past Black Canyon City, and no it is not a tourist stop.

"Wait for some traffic to clear and then we can get out, and we’ll make a quick run over to the spot," Nintzel explained. "We got our gap, okay."

Cars whip by as we try to walk fast through overgrown grass and bushes.

What looked like a small tree from a distance has now become much larger. It is not all that pretty, it isround and bushy. It is about 12 feet high and adorned with melon-sized ornaments and large makeshift cardboard candy canes, wrapped gift boxes and ribbons.

Nintzel said he remembers when he first saw it.

“My memory goes back to either the late '70s or the early '80s. I was a student at NAU, and I have memories of coming by and seeing the tree with decorations not as elaborate as you see now-a-days," Nintzel shared.

Nintzel said for years the decorations have popped up before Thanksgiving and come down mysteriously after New Years. He said the tree has become a highway icon, so much so that during a recent wildfire people came around to protect it.

“Flames got right to the base of the tree and some ADOT workers were here, some passersby, I think a firefighter or two, and they wound up being able to beat down the flames," said Nintzel.

Under the tree is a makeshift irrigation system. It has four small barrels with plastic tubing used to water the tree. Nintzel said it is a mystery who does all this.

“Really that many years and you don’t know?" I asked.

"Well I can tell you I’ve had people tell me that they know who does the decorating of this tree, but they have never told me who it is, and I kind of like that because I like to keep the mystery alive," said Nintzel.

It is a long stretch between northern Arizona and the Valley. So, a mysterious Christmas tree in the middle of nowhere may just add a bit of holiday spirit for that long ride home.